Correct Option
The correct option is 2 and 3 only.
Explanation
According to the Theory of Plate Tectonics, the interaction between lithospheric plates occurs along their margins. These margins are classified into three types based on the relative movement of the plates: divergent, convergent, and transform boundaries. These interactions determine whether the crust is created, destroyed, or conserved.
Statement-wise Analysis
- Statement 1 is Incorrect. Divergent boundaries occur when two tectonic plates move away from each other. As the plates separate, magma rises from the mantle to fill the gap, solidifying to form new crust. Therefore, these are known as constructive margins, not sites where crust is destroyed. An example is the Mid-Atlantic Ridge.
- Statement 2 is Correct. Convergent boundaries are formed when two plates move towards each other. During this collision, the denser plate typically subducts beneath the lighter plate and enters the mantle, where it is consumed. Consequently, crust is destroyed at these zones, which is why they are termed destructive margins.
- Statement 3 is Correct. Transform boundaries occur where two plates slide horizontally past one another. In this process, there is no vertical movement involving the upwelling of magma or subduction. Therefore, the crust is neither produced nor destroyed. These are referred to as conservative margins. An example is the San Andreas Fault.
Key Takeaway
Divergent boundaries are constructive (new crust is formed), Convergent boundaries are destructive (crust is consumed), and Transform boundaries are conservative (crust is neither created nor destroyed).